Regulating temperature

Ray

I have a medium BGE and I don't think I really understand the fine tuning of the temperature. For example, if the temp is 300 and I want to drop it to 250 do I reduce the bottom vent opening or open/close the slide top on the Egg? When you open the top of the egg are you letting more hot air out and reducing the temp or are you "drawing"
more air and getting the inside temp hotter? I usually muddle through by trial and error and eventually accomplish what I want- however it would be nice to know the right way to control the temp.
Thanks for any help you may give-[p]Ray Dickinson

Nature Boy

Ray,
Opening the lid provides oxygen to the fire in mass quantities, and tends to increase the dome temp ultimately. The more you open, the hotter the fire gets. One of the keys to successful temp control is to minimize or eliminate opening the lid.[p]Once the ceramics are heated through, dropping the temp from 300 to 250 takes time....after the fire is reduced, the ceramics take time to cool. [p]You'll have it down in no time!
NB

Ray

Nature Boy,
Thanks for the help-
Ray

Tim M

Ray,[p]NB is correct with his advice - once you go over it's hard to get it to drop back, and the longer it's over the harder it will be. [p]As far as the relation between the bottom vent and the slide daisy top, there is no "single way" to do it. You can do "this or that" and get the job done. That said, lets assume you will use the daisy part only and the bottom vent. Once the fire is started you close the bottom vent to about 1-2" and the daisy top is open (only the daisy part). This setup will give you a max temp of 375-400 deg. The daisy top won't allow any more even if you open the vent more. As time passes it will get higher but not much. [p]Closing the bottom vent affects the fire more than closing the daisy top (although either will drop the dome temp in time)so fine tuning is easier with the daisy part. Get close with the bottom, fine tune with the top. Air entering the bottom vent will expand many times while in the Egg so you get much more out than went it (in volume). The daisy will leak a little so even if it's closed the Egg will force air past it - the bottom vent, however, will snuff the fire if closed for very long. If you need to drop the temp, start by closing the daisy all the way. If it's a big drop, close the bottom vent more, but always leave a crack or the fire will go out and when you get to the desired temp - you will drop below it.[p]Tim

BlueSmoke

Tim M,
Didn't somebody come up with an "automatic" bottom vent opener/closer? Seems like it was based on a cordless drill and way more electronics than I can even begin to remember. The idea was to hit near your target temp (to set the daisy where you wanted it) and then let the electronics take over to lock on the target.

Tim M

BlueSmoke,[p]That was Supreme Commander. His Rube Goldberg design was odd.[p]Tim

JimW

Tim M,
I think he had way too much time on his hands too.
JimW

BlueSmoke

JimW,
Maybe too much time, but think about it... You could run your egg dang near 24/7, stopping only to vacuum out the ash and refuel. (I've got how long till retirement??????)

Ray

Tim M,
Thanks for the expert advice-
Ray

Unknown

Ray,
You have used a name I have registered in the user's profile section. You may want to change yours to avoid confusion, since I have gotten several e-mails I am sure were meant for you.
Ray

Rayddd

The First Ray,[p]Thanks for the info - I will make the change.[p]Ray D.